how do i link together all internal post links for SEO

how do i link together all internal post links for SEO traffic.
i believe internal link struture will be very nice for SEO.

I think when google starts indexing, it will begin from the home page and can only index any page or post that is linked to the home page.

Now assuming i created 3 post like post1.htm1,post1.htm2,post3.html etc. must i link them physically to the home page so as to be indexed along by the Google or should i leave the post as being published.
thanks

Linking internal pages, called deep linking, can indeed help with your SEO. That being said, I would only link them when appropriate, usually due to relevance of topic, rather than just blindly linking every page.